The present invention pertains to a resilient, flexible, compressible, biocompatible prosthesis insertable into the stomach to effect weight loss over a controlled period.
The incidence of obesity and its associated health-related problems have reached epidemic proportions in the United States. See, for example, P. C. Mun et al., xe2x80x9cCurrent Status of Medical and Surgical Therapy for Obesityxe2x80x9d Gastroenterology 120:669-681 (2001). Recent investigations suggest that the causes of obesity involve a complex interplay of genetic, environmental, psycho-behavioral, endocrine, metabolic, cultural, and socioeconomic factors. Severe obesity is frequently associated with significant comorbid medical conditions, including coronary artery disease, hypertension, type II diabetes mellitus, gallstones, nonalcoholic steatohepatitis, pulmonary hypertension, and sleep apnea.
Estimates of the incidence of morbid obesity are approximately 2% of the U.S. population and 0.5% worldwide. Current treatments range from diet, exercise, behavioral modification, and pharmacotherapy to various types of surgery, with varying risks and efficacy. In general, nonsurgical modalities, although less invasive, achieve only relatively short-term and limited weight loss in most patients. Surgical treatments include gastroplasty to restrict the capacity of the stomach to hold large amounts of food, such as by stapling or xe2x80x9cgastric banding.xe2x80x9d Other surgical procedures include gastric bypass and gastric xe2x80x9cballoonsxe2x80x9d which, when deflated, may be inserted into the stomach and then are distended by filling with saline solution.
The need exists for cost effective, less invasive interventions for the treatment of morbid obesity.
The present invention provides a novel system for treatment of morbid obesity by use of a bioabsorbable gastric prosthesis placed in the stomach through a minimally invasive procedure. The prosthesis takes up space in the stomach so that the stomach can hold a limited amount of food, and preferably exerts pressure on the upper fundus to create a sensation of being full. The material of the prosthesis can be selected to degrade over a predetermined period and pass out of the patient without additional intervention.
In the preferred embodiment, the prosthesis is a porous weave of bioabsorbable filaments having an open mesh configuration. The prosthesis can be formed from a cylindrical stent, such as by reverting the ends of the cylinder and joining them at the center. The filaments preferably have memory characteristics tending to maintain an oblate shape with sufficient resiliency and softness so as not to unduly interfere with normal flexing of the stomach or cause abrasion of the mucus coat constituting the inner lining of the stomach. The prosthesis may be free floating in the stomach, but is shaped so as to be biased against the upper fundus, or it may be tacked in position adjacent to the fundus by bioabsorbable sutures.